These options allow you to modify the behavior of any installed plugins. Note that the list of plugins displayed will depend on which plugins KMyMoney found when it started. It does not matter whether the plugin was compiled as part of the application or added as a separate package.
For most plugins, the only choice is to enable or disable it, as indicated by the checkbox next to the name of the plugin. In addition, there is also an () button for each, which will show the plugin version and author. Further information on configuring and using these plugins may be found in the separate sections for CSV Import and OFX Import plugins. It is also true for the Reconciliation report, although that report is only a minor part of the larger reconciliation process. The one plugin that does require a configuration step is the Print Check plugin.
This plugin is included with the source of KMyMoney, and should always be enabled. It allows printing of a check based on the data from a selected transaction, with the layout controlled by an html template. You need to use a template which is matched to your pre-printed checks. When you click on the () button , the Print check configuration dialog is displayed. At the top is a text box for the path to the selected template. To the right of that is a button which brings up a file chooser, to select an alternative template file.
A template file is an html file, in which specific strings are used to reference the fields from the transaction and from the current account and institution to show where they will be printed on the check. KMyMoney is shipped with some sample template files. You should either be able to use one of them, or modify one to suit your needs. When the default template is selected, the configuration dialog will show you the directory which contains the sample files.